ath9k: implement .get_antenna and .set_antenna

On MIMO chips this can be used to enable/disable hardware chains, ensuring
that the MCS information is updated accordingly.
On non-MIMO chips with rx diversity (e.g. 9285), this configures the rx
input antenna.

Signed-off-by: Felix Fietkau <nbd@openwrt.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

4 files changed, 99 insertions, 8 deletions

diff --git a/drivers/net/wireless/ath/ath9k/ath9k.h b/drivers/net/wireless/ath/ath9k/ath9k.h
index b2992d4097c3..0fb4a26f8979 100644
--- a/drivers/net/wireless/ath/ath9k/ath9k.h
+++ b/drivers/net/wireless/ath/ath9k/ath9k.h
@@ -649,6 +649,7 @@ struct ath_softc {
         struct ath_descdma txsdma;
 
         struct ath_ant_comb ant_comb;
+        u8 ant_tx, ant_rx;
 };
 
 void ath9k_tasklet(unsigned long data);
@@ -669,6 +670,7 @@ int ath9k_init_device(u16 devid, struct ath_softc *sc,
                     const struct ath_bus_ops *bus_ops);
 void ath9k_deinit_device(struct ath_softc *sc);
 void ath9k_set_hw_capab(struct ath_softc *sc, struct ieee80211_hw *hw);
+void ath9k_reload_chainmask_settings(struct ath_softc *sc);
 
 void ath_radio_disable(struct ath_softc *sc, struct ieee80211_hw *hw);
 bool ath9k_uses_beacons(int type);
diff --git a/drivers/net/wireless/ath/ath9k/init.c b/drivers/net/wireless/ath/ath9k/init.c
index be302fbdc3dc..9b34c4bab937 100644
--- a/drivers/net/wireless/ath/ath9k/init.c
+++ b/drivers/net/wireless/ath/ath9k/init.c
@@ -653,9 +653,22 @@ static void ath9k_init_txpower_limits(struct ath_softc *sc)
         ah->curchan = curchan;
 }
 
+void ath9k_reload_chainmask_settings(struct ath_softc *sc)
+{
+        if (!(sc->sc_ah->caps.hw_caps & ATH9K_HW_CAP_HT))
+                return;
+
+        if (sc->sc_ah->caps.hw_caps & ATH9K_HW_CAP_2GHZ)
+                setup_ht_cap(sc, &sc->sbands[IEEE80211_BAND_2GHZ].ht_cap);
+        if (sc->sc_ah->caps.hw_caps & ATH9K_HW_CAP_5GHZ)
+                setup_ht_cap(sc, &sc->sbands[IEEE80211_BAND_5GHZ].ht_cap);
+}
+
+
 void ath9k_set_hw_capab(struct ath_softc *sc, struct ieee80211_hw *hw)
 {
-        struct ath_common *common = ath9k_hw_common(sc->sc_ah);
+        struct ath_hw *ah = sc->sc_ah;
+        struct ath_common *common = ath9k_hw_common(ah);
 
         hw->flags = IEEE80211_HW_RX_INCLUDES_FCS |
                 IEEE80211_HW_HOST_BROADCAST_PS_BUFFERING |
@@ -693,6 +706,16 @@ void ath9k_set_hw_capab(struct ath_softc *sc, struct ieee80211_hw *hw)
         hw->sta_data_size = sizeof(struct ath_node);
         hw->vif_data_size = sizeof(struct ath_vif);
 
+        hw->wiphy->available_antennas_rx = BIT(ah->caps.max_rxchains) - 1;
+        hw->wiphy->available_antennas_tx = BIT(ah->caps.max_txchains) - 1;
+
+        /* single chain devices with rx diversity */
+        if (ah->caps.hw_caps & ATH9K_HW_CAP_ANT_DIV_COMB)
+                hw->wiphy->available_antennas_rx = BIT(0) | BIT(1);
+
+        sc->ant_rx = hw->wiphy->available_antennas_rx;
+        sc->ant_tx = hw->wiphy->available_antennas_tx;
+
 #ifdef CONFIG_ATH9K_RATE_CONTROL
         hw->rate_control_algorithm = "ath9k_rate_control";
 #endif
@@ -704,12 +727,7 @@ void ath9k_set_hw_capab(struct ath_softc *sc, struct ieee80211_hw *hw)
                 hw->wiphy->bands[IEEE80211_BAND_5GHZ] =
                         &sc->sbands[IEEE80211_BAND_5GHZ];
 
-        if (sc->sc_ah->caps.hw_caps & ATH9K_HW_CAP_HT) {
-                if (sc->sc_ah->caps.hw_caps & ATH9K_HW_CAP_2GHZ)
-                        setup_ht_cap(sc, &sc->sbands[IEEE80211_BAND_2GHZ].ht_cap);
-                if (sc->sc_ah->caps.hw_caps & ATH9K_HW_CAP_5GHZ)
-                        setup_ht_cap(sc, &sc->sbands[IEEE80211_BAND_5GHZ].ht_cap);
-        }
+        ath9k_reload_chainmask_settings(sc);
 
         SET_IEEE80211_PERM_ADDR(hw, common->macaddr);
 }
diff --git a/drivers/net/wireless/ath/ath9k/main.c b/drivers/net/wireless/ath/ath9k/main.c
index 19c78be3dc41..c8ac2ce61ffe 100644
--- a/drivers/net/wireless/ath/ath9k/main.c
+++ b/drivers/net/wireless/ath/ath9k/main.c
@@ -281,6 +281,22 @@ static bool ath_complete_reset(struct ath_softc *sc, bool start)
                         ath_start_ani(common);
         }
 
+        if (ath9k_hw_ops(ah)->antdiv_comb_conf_get && sc->ant_rx != 3) {
+                struct ath_hw_antcomb_conf div_ant_conf;
+                u8 lna_conf;
+
+                ath9k_hw_antdiv_comb_conf_get(ah, &div_ant_conf);
+
+                if (sc->ant_rx == 1)
+                        lna_conf = ATH_ANT_DIV_COMB_LNA1;
+                else
+                        lna_conf = ATH_ANT_DIV_COMB_LNA2;
+                div_ant_conf.main_lna_conf = lna_conf;
+                div_ant_conf.alt_lna_conf = lna_conf;
+
+                ath9k_hw_antdiv_comb_conf_set(ah, &div_ant_conf);
+        }
+
         ieee80211_wake_queues(sc->hw);
 
         return true;
@@ -2379,6 +2395,59 @@ static int ath9k_get_stats(struct ieee80211_hw *hw,
         return 0;
 }
 
+static u32 fill_chainmask(u32 cap, u32 new)
+{
+        u32 filled = 0;
+        int i;
+
+        for (i = 0; cap && new; i++, cap >>= 1) {
+                if (!(cap & BIT(0)))
+                        continue;
+
+                if (new & BIT(0))
+                        filled |= BIT(i);
+
+                new >>= 1;
+        }
+
+        return filled;
+}
+
+static int ath9k_set_antenna(struct ieee80211_hw *hw, u32 tx_ant, u32 rx_ant)
+{
+        struct ath_softc *sc = hw->priv;
+        struct ath_hw *ah = sc->sc_ah;
+
+        if (!rx_ant || !tx_ant)
+                return -EINVAL;
+
+        sc->ant_rx = rx_ant;
+        sc->ant_tx = tx_ant;
+
+        if (ah->caps.rx_chainmask == 1)
+                return 0;
+
+        /* AR9100 runs into calibration issues if not all rx chains are enabled */
+        if (AR_SREV_9100(ah))
+                ah->rxchainmask = 0x7;
+        else
+                ah->rxchainmask = fill_chainmask(ah->caps.rx_chainmask, rx_ant);
+
+        ah->txchainmask = fill_chainmask(ah->caps.tx_chainmask, tx_ant);
+        ath9k_reload_chainmask_settings(sc);
+
+        return 0;
+}
+
+static int ath9k_get_antenna(struct ieee80211_hw *hw, u32 *tx_ant, u32 *rx_ant)
+{
+        struct ath_softc *sc = hw->priv;
+
+        *tx_ant = sc->ant_tx;
+        *rx_ant = sc->ant_rx;
+        return 0;
+}
+
 struct ieee80211_ops ath9k_ops = {
         .tx                 = ath9k_tx,
         .start              = ath9k_start,
@@ -2405,4 +2474,6 @@ struct ieee80211_ops ath9k_ops = {
         .tx_frames_pending  = ath9k_tx_frames_pending,
         .tx_last_beacon     = ath9k_tx_last_beacon,
         .get_stats          = ath9k_get_stats,
+        .set_antenna        = ath9k_set_antenna,
+        .get_antenna        = ath9k_get_antenna,
 };
diff --git a/drivers/net/wireless/ath/ath9k/recv.c b/drivers/net/wireless/ath/ath9k/recv.c
index 9c7f905f3871..8d3e19dfe7db 100644
--- a/drivers/net/wireless/ath/ath9k/recv.c
+++ b/drivers/net/wireless/ath/ath9k/recv.c
@@ -1950,7 +1950,7 @@ int ath_rx_tasklet(struct ath_softc *sc, int flush, bool hp)
                         ath_rx_ps(sc, skb);
                 spin_unlock_irqrestore(&sc->sc_pm_lock, flags);
 
-                if (ah->caps.hw_caps & ATH9K_HW_CAP_ANT_DIV_COMB)
+                if ((ah->caps.hw_caps & ATH9K_HW_CAP_ANT_DIV_COMB) && sc->ant_rx == 3)
                         ath_ant_comb_scan(sc, &rs);
 
                 ieee80211_rx(hw, skb);